The rise of FrankenEngine - An engine for the VP-21

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WonderousMountain

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Kawasaki's long block is 80mm, pair that with standard Jabiru Pistons
and you are single digit CC's shy of 1200. Put that in a Magnesium case.
180 - 540 firing. Ba-boom ahh.
 

addicted2climbing

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I just skimmed this but unsure if the Citroen 2CV was mentioned. Its been proven to work well with a PSRU and the plans can be had from the guy who sells the ULF-2. I always thought that a smaller O-100 type engine could be made from the 2CV pistons (Visa has higher CC) and they are cheap and Nikasil.

Also I just ran across this and it looks promising but its way too big. Wonder if a smaller .75L engine is in the works. Radial Motion – manufacturing light, powerful radial engines in South Australia

Also to address another post on here that mentioned the O-100 would rely on legacy parts with limited supply and production I know that no longer to be the case. I met with Pete 2 weeks before passing and he showed me an engine on a table with all the parts laid out ready to assemble. It had custom Carrillo Rods & Pistons and a few other bits to get away from being tied to Continental. He was looking into certification and that engine would likely have used legacy parts but for the Experimental kit the Carrillo option was there.
 

blane.c

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With two cylinders a single crank throw gives you a pop, pop, wheeze, wheeze engine.

Two throws gives you pop, wheeze, pop, wheeze.

So two throws or one throw?
 

blane.c

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I just skimmed this but unsure if the Citroen 2CV was mentioned. Its been proven to work well with a PSRU and the plans can be had from the guy who sells the ULF-2. I always thought that a smaller O-100 type engine could be made from the 2CV pistons (Visa has higher CC) and they are cheap and Nikasil.

Also I just ran across this and it looks promising but its way too big. Wonder if a smaller .75L engine is in the works. Radial Motion – manufacturing light, powerful radial engines in South Australia

Also to address another post on here that mentioned the O-100 would rely on legacy parts with limited supply and production I know that no longer to be the case. I met with Pete 2 weeks before passing and he showed me an engine on a table with all the parts laid out ready to assemble. It had custom Carrillo Rods & Pistons and a few other bits to get away from being tied to Continental. He was looking into certification and that engine would likely have used legacy parts but for the Experimental kit the Carrillo option was there.
Finding “new” rocker arms for the little Continental is difficult at best, if Carrillo was going to make those it would make the engine attractive to more people.
 

blane.c

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Of course you are getting a bit of natural prop extension which would offset a bit of the weight if a V twin needed a longer prop extension and the intake and exhaust might be lighter both on one side of the engine?
 

dog

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Inline twin,with 4 throws,50 hp,diesel.
Developed by Neander with yanmar for an outboard motor,has been put in bikes.
 

patrickrio

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Inline twin,with 4 throws,50 hp,diesel.
Developed by Neander with yanmar for an outboard motor,has been put in bikes.
interesting. Since it has 2 crank shafts that are then geared to final shaft, I assume it would not be too difficult to have different ratios for the final gearing.

high torque at low rpm, low power pulses, can gear to low propeller rpm
 

Mark Gipson

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How about designing VW heads using electronically actuated valves thus eliminating the cam, pushrods, pushrod tubes and seals, rockers, cam chain/gears? The weight savings could be significant. Also allows variable valve timing and repositioning the intake and exhaust valve locations to suit the application.

 

Aviacs

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Seems from reading above that the initial design question boils down, as it always has for aviation motivation, which philosophical choice to make:

1.) optimize a slow revving (direct drive) engine with adequate torque to operate between 2700 & 3,000 rpm tops =>"large" displacement. Focus of design efforts = weight reduction while maintaining adequate strength & stiffness for durability. A boxer design seems practical for many apps in terms of streamlining (crank location) & perhaps TV issues.

2.) design a reliable 15lb PSRU for any number of small, relatvely light, industrial or MC type "medium" displacement motors optimized for 40 HP at something between 4,000 to 5,000 steady state operation. Bugaboo seems to be TV. Though successful iterations exist, Rotax 912 e.g.

smt
 

Vigilant1

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Seems from reading above that the initial design question boils down, as it always has for aviation motivation, which philosophical choice to make:

2.) design a reliable 15lb PSRU for any number of small, relatvely light, industrial or MC type "medium" displacement motors optimized for 40 HP at something between 4,000 to 5,000 steady state operation. Bugaboo seems to be TV. Though successful iterations exist, Rotax 912 e.g.
Assuming this is still a 4 stroke, if the small displacement + PSRU path is taken, then we'll need to budget some weight for liquid cooling (oil or water/glycol) as well. That small displacement 5000 rpm screamer won't have sufficient cylinder head area for effective air cooling at high continuous HP. Heat exchanger, hoses , pumps, it all adds up. At these small power levels, the weight needed for liquid cooling ancillaries is proportionally greater than it is for higher HP installations.
 

dog

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Many of the motors that meet the op spec are repurposed industrial motors,and that though there have been quite a few attempts to develope an aviation specific design,none of these attempts has been a growing success.
So then a clean sheet motor that does meet the op requirement and is marketed to power sports and industrial applications from day one.
Air cooled
Mountable any which way.
Dry sump,reconfigurable intigral lines,(plugs),
and tank mounting.
Fuel injected.Electronic ignition.Carb option costs more may not work depending on mounting position.
Starting options,pull,electric,none(prop,push)
Cooling option for stationary,ducts plus fan.
Cast in stone that the lightest weight version
comes in at under 2lb/hp.
Crank options,that include a "blank" flywheel end.
Case options with blank "thick" flywheel end.
Open source files for cnc .
Company hosted site for any and all open source projects,forum,etc.
 

David L. Downey

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I have thought for some time that a two cylinder Flathead would be perfect. The trade off of weight for more cubic inches and a flat head with relatively low compression also lowers the parts count. It also makes two plugs per cylinder easy and is narrower than a overhead valve engine. The D-motor flathead is enjoying some success in the eu.
second that thought. The D-motor had fantastic promise for the flathead reason until it priced itself right out of the stratosphere then went drone only
 

galapoola

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I just skimmed this but unsure if the Citroen 2CV was mentioned. Its been proven to work well with a PSRU and the plans can be had from the guy who sells the ULF-2. I always thought that a smaller O-100 type engine could be made from the 2CV pistons (Visa has higher CC) and they are cheap and Nikasil.

Also I just ran across this and it looks promising but its way too big. Wonder if a smaller .75L engine is in the works. Radial Motion – manufacturing light, powerful radial engines in South Australia

Also to address another post on here that mentioned the O-100 would rely on legacy parts with limited supply and production I know that no longer to be the case. I met with Pete 2 weeks before passing and he showed me an engine on a table with all the parts laid out ready to assemble. It had custom Carrillo Rods & Pistons and a few other bits to get away from being tied to Continental. He was looking into certification and that engine would likely have used legacy parts but for the Experimental kit the Carrillo option was there.
Just watched the “first start” video and have a question. Why isn’t that 3 cylinder radial shaking like the Verner 3? Was it bolted down to an unmovable test stand? it seemed oh so smooth.
 

Hot Wings

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second that thought. The D-motor had fantastic promise for the flathead reason until it priced itself right out of the stratosphere then went drone only
My current path is down the flat head trail. At the RPM of a direct drive we can accept the lower volumetric efficiency. The A-40 proves that it can fly a plane with 40 (EDIT: hate hot keys and I now have to edit an incomplete post) ish Hp.

The big advantage is narrow width with parts count being a close second. The attached pic is my CAD scribble sheet...................This project is why I learned SW many years ago.Flat head.JPG
The left is basic VW the right is flat head with Harley cylinder.....and part of that head suppressed.
 
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